Fuse.



C. S. PRICE.

FUSE.

APPLICATION FILED AuG.3,19Ia.

Lf?. mme@ ,my 2, 1918.

entire CHARLES S. RCE, @F BUTHERFORD, NEV JERSEY, ASSIGNOR TO WESTERN ELEGTBC GOMNY? NCOEQB-ATED, 9F NEW YORK, N. Y., .A CSRPORATION 0F NEW YORK.

FUSE.

Application led August 3,

To all whom t may concern:

Be it known that l, CHARLES S. PRICE, a citizen of the United States, residing at Rutherford, in the county of Bergen and State of New Jersey, have invented certain new and useful improvements in Fuses, of which the following is a full, clear, concise, and exact description.

This invention relates to thermal cut-outs or fuses for electric circuits of the type in which a fusible conductor of low melting point is ruptured by the heating eii'ect of the current passing through it whenever such current exceeds a predetermined value.

The object of this invention is to provide a fuse of relatively short length which will be efficient in operation and which will not introduce a dangerous fire hazard.

To accomplish this object the invention provides a fuse cartridge comprising a tubular sheath inclosing a fusible conductor and vented at or near one end, the fusible conductor being constructed or provided with means to insure that its rupture in operation will take place at or near 'the yend of the sheath opposite said'vent. interposed between the rupture point of the fusible conductor and the vented end of the sheath is a porous non-conducting material such as asbestos sleeving, which has been round to be very eilicient in breaking up the are and in absorbing and condensing the heated metal vapors generated by the vaporization of the fusible conductor.

As a further object in preventing the eX- pulsion of heated gases and in muifling the sound of the report due to the operation of the fuse on high potentials, an ad litional casing is rovided so arranged as to forni an air cham er about a fuse cartridge, such as described above, and having vents at the end opposite to the vented end of the cartridge.

The several features of this invention may be more readily understood by reference to the accompanying drawings, wherein Figure i is a sectional view of a fuse in which the rupture point of the fusible conductor is definitely located at one end, and at the opposite end of the fuse, vents are provided for the expulsion of heated gases, the intervening space being lled with e porous nonconducting material. Fig. 2 is a sectional view. of a fuse cartridge of the type shown Specification o1. Letters Patent.

Patented July 2, 1918.

191e. y serial .ua-112,989.

in Fig. l, having in addition an inclosing casing vented at the end away from the vented end in the fuse cartridge.

Referring to Fig. l of the accompanying drawings, l represents a tubular sheath of insulating material, such as fiber, inclosing a fusible conductor 2, which is connected between the metal end pieces 3. rihese end pieces7 which rnay be provided with nuts d for aid in securing the fuse in suitable niountings, are shown as spun into the insulating tube 17 but 'they may be fastened by any of the methods known to the art, such as by the use of pins extending through the tubes and into theend pieces, or by means of screws passing through the tube and threaded into the end pieces. Surrounding the fusible conductor for a portion of its length is a porous non-conducting non-combustible material 5. The remaining portion of the fusible conductor is surrounded by a tube 6 of insulating material, such as paper, so arranged as to provide an air space about the conductor. For the insulating material 5 asbestos sleeving has been found to be very efficient. This sleeving is allowed to come in contact with the fusible conductor, and by so doing conducts away a portion of the heat generated, allowing the portion of the fusible conductor passing through the tube 6 to attain the higher temperature, and thereby determine the point of rupture. Suitable vents 8 in the sheath 1 are so located that the heated gases generated by the rupture of the fusible conductor 2 are required to pass through practically the entire length of the asbestos sleeving before being expelled, and in so doing the metallic vapors are absorbed and chilled and the arc is broken up.

Referring to Fig. 2, a fuse cartridge is used of the same general nature as that shown in Fig. l. ln addition there are provided an inclosing casing 9 of insulating material, and metal end caps 10 adapted to make Contact with the end pieces 3 of the cartridge and to close the ends of the tubular casing. This casing is provided with an aperture or vent 11 at or near the end; away from the vents 8 in the sheath of the fuse cartridge. This construction provides an expansion air chamber 12 for muling the sound of the explosion resulting from sudden vaporization of the fusible conductor and for preventing the expulsion of heatedV metal vapors which mightconstitute'a dangeious re hazard.

l/Vhile the means shown heretofore described, for determining the ruptuiing point et the fuse consists in providing an ai? chamber at that point, the balance of the fusible eouductoil being suirounded and in intimate contact with a material which will conduct away part of the heat generated, it is of course obvious that other well-known ineens may he used, such, for exemple, es :restricting the @toss-section of the fusible eonduotoi at the desired rupture point.

TWhat is claimed is:

l. A protective device Comprising a tubuler sheath Vented at oi' near one end, metal caps inolcsing the ends of said sheath, a fusible conductor extending between said cepsand means 'foreausing the iupture of seid fusible conductor at a point neai= the non-vented end of the sheath.

2. A protective device comprising a tubular sheath vented at or near one end, 'metalcaps inclosing the 'ends of said sheath, a fusible conduetoi` extending between 'said caps, means for causing the rupture of said fusible conductor at a point neatI the non- Vvented end of the sheath, and a porous nonconducting material surrounding said con- Leases? ducter between its rupture point and seid vent.

3. A protective device comprising e tubu- "iaiA sheath Vented at oi near one end, a fusiole conductor therein, e non-conducting material surrounding and in intimate Contact with that portion of said conductor occupying the if'ented end of the sheath, aud a tube i insulating material surrounding but not making Contact with seid conductor at the non-vented end of the sheath, whereby the rupture of the fusible conductoi1 Will take place at seid non/ented end.

ll. rihe combination With'a fuse cartridge comprising a tuloulail sheatii vented at'or near one end, `a fusible conductor'theein, a porous non-condueting` material surroundin` said eonductor, and means for determi ing the ruptuie point of said conductor at or near the non-vented end of the sheath, of an inclosinf casing lagez1 in d'- azneter than and surounding said carti'idge so es to oim an interposedair space, said casing being vented at or neer the end opposite to the ventedend et said cartridge' sheath.

ln Witness whereof, 'heieunto subscribe my name this 27 day oi July, A. D. 1916.

CEAS. S. FLGE. y 

